Insulation materials are frequently used to reduce the transmission of heat and sound. In aircraft, for instance, insulation is typically used to protect occupants, cargo, equipment, or other components from extreme or otherwise adverse temperature and sound conditions. For example, aircraft engines can generate a substantial amount of heat and noise during operation. Moreover, aircraft frequently operate in very cold environments since the outside temperature decreases as altitude increases. It may also be desirable to insulate heat sources on military aircraft to reduce or eliminate heat signatures that could result in unwanted detection.